JP5037997B2 - Leading beam construction method and leading beam connection structure - Google Patents

Description

  The present invention relates to a method of leading beam construction capable of preceding construction of a supporting work between two tunnels when widening (cutting and expanding) between two parallel tunnels, and a tunnel lining member of the preceding beam. The present invention relates to a pre-cut beam joint structure to be joined to the joint.

  In order to construct an underground parking zone or an underground station between two parallel shield tunnels, various construction methods have been proposed as an inter-tunnel widening method for widening the space between both shield tunnels. For example, Patent Document 1 (Patent No. 2566162) Gazette) and Patent Document 2 (Japanese Patent No. 3096665).

  In particular, in Patent Document 1, when cutting and expanding between parallel tunnels, a pair of left and right horizontal support steel members are connected and extended so that the length can be adjusted, and the upper beam is adjusted by excavating the upper part between the parallel tunnels. After that, the construction method that constructs the ceiling slab, and installs the bottom beam between the floors of the parallel tunnels, and then places the cast-in-place concrete between the floors to construct the floor between the parallel tunnels is disclosed. Has been.

  In this construction method, neither the upper beam nor the lower beam is installed ahead of the parallel tunnel, and the upper beam is installed by excavating the upper part between the parallel tunnels. It is designed to be installed after excavating between parallel tunnels and removing the segments on both sides of the excavation space. Also, the beams are not designed to be joined to parallel tunnel segments.

Therefore, it is necessary to excavate between parallel tunnels for the installation of cut beams, and there is a problem that the parallel tunnels are displaced.
Japanese Patent No. 2566162 Japanese Patent No. 3096665

  An object of the present invention is a construction method in which a beam to be a supporting work at the time of widening can be pre-constructed before widening between two parallel tunnels, and the construction cost can be reduced from the tunnel without affecting the excavation process. It can be constructed efficiently, and the cutting beam can be stably joined to the lining material of the tunnel, so that it does not cause displacement of the tunnel, and it can be applied to large section tunnels with good economic efficiency, workability and safety. The object is to provide a leading beam construction method and a leading beam connection structure.

<Invention according to Claim 1 >
Prior to widening the space between two parallel tunnels , the preceding beam connection structure of the present invention covers both ends of the preceding beam installed so as to penetrate between these two tunnels. It is a leading beam connection structure that joins to a member, and joins the end of the leading beam to an erection member installed in the axial direction in the tunnel, and between the erection member and the lining member. The front end portion of the fastening member disposed along the beam is pin-coupled to a joining piece fixed to the lining member.

The preferable form is as follows.
<Invention according to Claim 2 >
A plurality of preceding cutting beams are joined to one erection member.

<Invention according to claim 3 >
As a fastening member, threaded reinforcing bars are installed at a plurality of locations around the preceding beam.

<Invention according to claim 4 >
A stuffing material is stuffed between the segment as the erection member and the lining member.

<Invention according to claim 5 >
The preceding cutting beam is a steel pipe, the angling member is die steel, a joining plate is fixed to the end of the steel pipe that is the preceding cutting beam, and the joining plate is joined to the flange of the die steel that is the raising member.

The effects of the present invention are as follows for each claim.
<Invention according to Claim 1>
Prior to widening between two parallel tunnels, both ends of the leading beam installed so as to penetrate between the two tunnels are connected to the lining member in both tunnels. The end of the preceding beam is joined to the erection member installed in the axial direction in the tunnel, and the end of the fastening member is disposed between the erection member and the lining member along the preceding beam. Since the part is pin-coupled to the joining piece fixed to the lining member, it can be stably joined to the lining member, and the displacement of the tunnel is reduced in both the compressing direction and the pulling direction as seen from the preceding cutting beam. In addition to not inviting, it is easy to remove.
Therefore, the present invention can be applied to a large section tunnel with good economic efficiency, workability and safety.

<Invention according to Claim 2 >
Since a plurality of preceding cutting beams are joined to one erection member, joining of the preceding cutting beams can be performed economically with good workability.

<Invention according to claim 3 >
Since the fastening member to the lining member is fastened to the lining member at each of the preceding cutting beams at a plurality of locations around it, an uneven load is applied to the end of the preceding cutting beam and the lining member. Can be joined together.

<Invention according to claim 4 >
Since the stuffing material is packed in the gap between the erection member and the lining member, the direction in which the erection member approaches the lining member (the direction of compression when viewed from the preceding beam) Can be restrained by the stuffing material, and the fastening between the erection member and the lining member can be performed stably.

<Invention according to claim 5 >
The prior art beam-to-beam connection structure according to the present invention can be realized by using common materials and simple joining means such as bolts / nuts or welding.

  Next, an embodiment of the present invention applied to a shield tunnel will be described in detail with reference to the drawings.

  FIG. 1 shows a cross section of a widened area for carrying out the present invention. In this example, the case where the space between two parallel shield tunnels 1 and 2 that will be an underground expressway is widened to form a split junction, and an upper support 3 with pipe roofs is constructed at both ends. The upper ground improvement 4 is given, and also the impermeable wall 5 is constructed on both sides. Two parallel shield tunnels 1 and 2 are constructed below the upper support 3. In this state, the leading beam construction method according to the embodiment of the present invention is configured to penetrate the leading beam 6 between the shield tunnels 1 and 2 as follows.

  Before constructing the leading beam 6, as shown in FIG. 2, in order to protect the periphery of the leading beam penetration part of both shield tunnels 1, 2, the ground is improved in advance by chemical injection or the like, and both shield tunnels 1・ Preliminary protective zones 7 and 8 along 2 are formed.

  One of the two shield tunnels 1 and 2, for example, as shown in FIG. 3, from the shield tunnel 2, a steel pipe that becomes the leading beam 6 is propelled by a small-diameter muddy water propulsion device 9 by a known small-diameter muddy water propulsion method, The preceding cutting beam 6 leading to the other shield tunnel 1 is installed through. Thereafter, in each shield tunnel 1, 2, the end of the preceding cutting beam 6 is joined to a segment that is a lining member as follows.

  FIGS. 4 to 9 show the preceding beam-to-beam connection structure on the shield tunnel 1 side, but only the direction of the shield tunnel 1 side is opposite to that of the shield tunnel 2 side, so only the shield tunnel 1 side will be described.

  Since the preceding cutting beam 6 is a steel pipe, a rectangular joining plate 10 is welded to the end of the leading cutting beam 6 as shown in FIG. 8, and for further reinforcement on both sides of the outer peripheral surface of the preceding cutting beam 6 (steel pipe). The reinforcing rib 11 is also welded.

  An angling member 12 made of H-shaped steel is installed in parallel to the axis of the shield tunnel 1, and the joining plate 10 of the preceding beam 6 is fastened to the flange 12 a with bolts and nuts, and the end portion of the preceding beam 6 Is erected and joined to the member 12. Since the erection member 12 is long along the shield tunnel 1, as shown in FIG. 6, a plurality of preceding cutting beams 6 are similarly joined to one erection member 12.

  The main girder 14 is provided at both ends and the middle of the steel segment 13 of the shield tunnel 1, and is an angle material on one side of the main girder 4 at both ends joined by the segments 13 and on both side surfaces of the intermediate main girder 14. The holed joint piece 15 is fixed (welded). In this example, since the erection member 12 and the segment 13 are fastened to the left and right and up and down of the main girder 14, the hole-joined pieces 15 are also changed up and down by changing the front and rear positions on each side of the main girder 14. It is provided in the place.

  The erection member 12 and the segment 13 are fastened by using threaded reinforcing bars 16 that are fastening members in each of the joint pieces 15 with holes. That is, for each of the joint pieces 15 with a hole, the tip of the threaded reinforcing bar 16 is loosely inserted into the hole of the joint piece 15 with a hole and the nut 18 via the washer 17 in order to make pin connection. At the side of the flank member 12, a holed support material 19, which is a mold material (steel material), is applied to the flange 12 b on the opposite side, and the rear end portion of the threaded reinforcing bar 16 is inserted into the hole, and the washer 20 is attached. And tighten with a nut 21.

  As a result, the erected member 12 and the segment 13 are fastened by the threaded reinforcing bars 16, and the tip of each threaded reinforcing bar 16 is pin-coupled to the joint piece 15 with a hole so as to be swingable. No heavy load is applied. Such fastening is performed on the left and right and up and down around the end of the leading beam 6 and also between the leading beam 6 and the leading beam 6.

  At the place (each main girder 14) where the erection member 12 and the segment 13 are fastened, the stuffing material 22 such as mortar is stuffed into the gap between the flange 12a of the erection member 12 and the segment 13. In addition, a reinforcing member 23 is installed between the flanges 12a and 12b on both sides of the joining portion between the flange 12a of the erection member 12 and the joining plate 10 of the preceding cutting beam 6.

  The leading beam 6 serves as a lower support for stably connecting the shield tunnels 1 and 2 by joining both ends thereof to the segments 13 of the shield tunnels 1 and 2 in this way.

  In FIG. 1, the lower support by the leading beam 6 is excavated below the upper support 3 by the pipe roof, the intermediate pile 24 is constructed, and the space between both shield tunnels 1 and 2 is expanded. Although it is removed after the housing is constructed, the preceding beam 6 can be easily removed because it has the above-described joint structure.

In the above embodiment, the steel pipe is used as the leading beam, the H-shaped steel is used as the erection member, and the threaded reinforcing bar is used as the fastening member. However, the present invention is not limited to this. May be used.
The present invention can also be applied to tunnels other than shield tunnels.

It is sectional drawing of the widened area which implements this invention. It is sectional drawing which shows performing ground improvement in order to protect the circumference | surroundings of the preceding beam penetration part of both shield tunnels before construction of a preceding beam. It is sectional drawing which shows the state which constructs a preceding cutting beam from the inside of a shield tunnel by a small-diameter muddy water propulsion method. It is sectional drawing of the perpendicular direction which shows an example of the precedent beam connection structure by this invention. It is the enlarged view. It is sectional drawing of a horizontal direction. It is the one part enlarged view. It is a front view of the junction part of the flange of an erection member and the edge part of a preceding cutting beam. It is sectional drawing of the state which stuffed the stuffing material in the clearance gap between a provoking member and a segment.

Explanation of symbols

1 and 2 Shield tunnel 3 Upper support 4 Upper ground improvement 5 Impermeable wall 6 Leading beam 7 and 8 Advance protection zone 9 Small-diameter mud propulsion machine 10 Joint plate 11 Reinforcement rib 12 Raising member 12a and 12b Flange 13 Segment 14 Main Girder 15 Joint 16 with Hole 16 Threaded Reinforcement 17 Washer 18 Nut 19 Percussion Material 20 with Washer 21 Nut 22 Stuffing Material 23 Reinforcement Material 24 Intermediate Pile

Claims (5)

Prior to widening between two parallel tunnels, both ends of the leading beam installed so as to penetrate between the two tunnels are connected to the lining member in both tunnels. The end of the preceding beam is joined to the erection member installed in the axial direction in the tunnel, and the end of the fastening member is disposed between the erection member and the lining member along the preceding beam. The leading beam connecting structure , wherein the portion is pin-coupled to a joining piece fixed to the lining member . Prior Setsuhari junction structure of claim 1, wherein a plurality of the preceding Setsuhari is joined to one of the wale member. The preceding cut beam joining structure according to claim 1 or 2 , wherein a threaded reinforcing bar is installed as a fastening member at a plurality of locations around the preceding cut beam. During the segment of the wale member and lining member, prior Setsuhari joint structure according to any one of claims 1 to 3, characterized in that the packing material is packed. The leading cutting beam is a steel pipe , the flank member is die steel, the joining plate is fixed to the end of the steel pipe that is the leading piercing beam, and the joining plate is joined to the flange of the die steel that is the bulging member. The preceding cut beam joint structure according to any one of claims 1 to 4 .

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